Apparatus for and method of treating asphalt solutions for the production of asphalt cement and the recovery of the lighter products.



F. H. DUNHAM.

APPARATUS FOR AND METHOD OF TREATING ASPHALT SOLUTIONS FORTHE PRODUCTION OF ASPHALT CEMENT AND THE RECOVERY OF THE LIGHTER PRODUOTS.

' APPLICATION FILED FEB.18, 1908.

1,003,040. Patented Sept. 12,1911. j

TED STATES PATENT OFFICE. A

FRANKLIN H. DUNHAM, OE LOS ANGELES, CALIFORNIA.

APPARATUS FOR :AND METHOD OF TREATING ASPHALT SOLUTIONS FOR THE PRODU TION OF ASPHALT CEMENT AND THE RECOVERY OI THE LIGHTER PRODUCTS Specification of Letters Patent.

Patented Sept. 12, 1911.

Application filed February18, 1908. Serial No. 416,611.

To all whom it may concern:

Be it known that I, FRANKLIN H. DUN- nau, a citizen of the United States, residing at Los Angeles, in the county of Los Angcles and State of California, have invented a new and useful Apparatus for and Method of Treating Asphalt Solutions for the Production of Asphalt Cement and the Recovery of the Lighter Products, of which the following is a specification.

This invention relates to the treatment of certain crude hydrocarbon oils found in Southern California, Texas, Louisiana and elsewhere and commonly known as oils having an asphaltic base. My investigations show that these oils are asphalt solutions and that the asphalt therein is held in suspension by'lighter hydrocarbon oils, which act as solvents of the asphaltum. There is usually also found in these oils a proportion of sulfur in chemical combination with the heavier hydrocarbons. T have discovered that by proper treatment of said crude hydrocarbon oils, the lighter constituents 25 can be removed without affecting the struc- -any stage of the process, of any extraneous substance, solution or vapor.

T depart from the ordinary method and from the ordinary apparatus in various particulars which will be more fully exemplified and set forth in the subjoined detailed specification.

T have discovered that by providing an extractor devoid of the customary dome and from which there are no vapor outlets that extend materially above the level of. the

process. ture of the asphalt and that when so re-.,

moved a practically pure asphalt cement main body of the extractor, and arranging a pan in the chamber of the extractor between the levels of upper and lower vapor outlets, and charging the pan with hot asphalt solution, that a tendency heretofore existing to carry off vapors that might condense within the extractor chamber is in a measure done away with and that by keeping the temperature comparatively low, much of the condensation of the hydrocarbon vapors that has heretofore been accomplished only outside of the extractor shell, can be caused to occur inside the extractor, sothat by collecting and carrying 05? the same, and by collecting and condensing the vapors that find their way to the top of the main body of-the extractor, without any extra aid as by-an elevated pipe or dome a maximum amount of hard cementcan be obtained in a minimum amount of time without loss of the hydrocarbon vapors.

The accompanying drawings illustrate my newly-invented apparatus which is adapted for carrying on my newlydiscovered Figure 1 is a longitudinal vertical section of apparatus embodying my improved means adapted for carrying on my newly-discovered method. Fig. 2 is a plan of said apparatus. Fig. 3 is a fragmental cross-section of the same on line m Figs. land 2, looking to the left. I

1 designates the extractor in the form of a cylindrical shell which may, be of any suitable dimensions, as for instance, ten feet in diameter and. twenty-two feet in length; the same being set in a furnace-wall, 2, of ordinary construction and provided with means as the fluid fuel burner 3 for supplying heat to the lower'half of the shell.

The shell 1 may have a slant or slope fromfront to rear end suflieient for drainage; for instance, a slope of six inches in 22 feet.

The shell is designed to contain a suit-able charge, viz., 100 barrels, more or less, of the asphaltic oil to be treated and the material in such charge will be kept fluid by the heat as the lighter oils are eliminated and the asphalt cement produced.

4t designates a perforated suction-p pe having orifices a at its under side to receive the fluid material at the bottom of the extractor.

5 designates a pump connected with the higher end of the pipe 4 to draw liquid through such pipe .from the bottom .of the extractor and'todischargeit into an evaporating pan 6 1ocated in the extractor, preferably about midway between the horizontal axial plane of the extractor and the 'top' of the extractor. 7

7 is a pipe leading from the pump to discharge into the evaporating pan 6 so that at the level therein at which the pan is stationed.

9 designates troughs arranged along the median portionof the shell of the extractor for the purpose of collecting the heavier vapors, and conducting them out of the extractor together- With the lighter oils that may collect on and flow as condensate down the sides of the shell, and conveying such vapors and condensate topip'es 10 by which they are drained off to any suitable receptacle, not shown, provided to retain them.

Said troughs 9 may be constructed parallel with the axis of the cylindrical extractor or shell 1, and consequently will slope to the 7 rear in the same degree as the shell,

11 designates outlets for the lighter I vapors distilled from the oil supplied to the extractor. These outlets may be of any desired size and number i and lead to any form of receptacle, not shown, adapted for the recovery and retention or storage of the vapors 1n their vaporous or condensed form.

'12 designates a valved draw-off for the hot asphalt cement.

An important feature in the construction of this extractor is the location of the outlets for the removal of the vapors, care being taken that said-outlets are below and do not extend above the level of the top of the cylinder'or main body which forms the extractor; the purpose of this being to remove the lighter'vapors from the extractor at a comparativelylow-level and as soon as 1quid, so that'they will not pile up inside the extractor to compress'the vapors below and cause the same to precipitate and return to the charge of hydrocarbon.

The vaporized liquids that are capable of condensing withinthe chamber of the ex tractor above the level of the hot oil from which the vapors have been evolved will contemperatures pressure range from 650 to 750 degrees racticable after they have evolved from the dense upon the inside surface of the extractor and such condensed liquids will flow wardly into the troughs along the side of the shell and thence out of the shell. I have discovered that in the present processes of reducing asphaltic oils in which the employed at atmospheric Fahrenheit, the .efiect of such heat 1s to cause a destructive .distillation of a portion of the asphalt, and that such portion is driven ofl in the form of vapor to condense .as an oil which proves to be no-better than,

and which commands no better price than crude oil,- thus involving considerable loss. Such product heretofore has been found to be very deficient in heating power, and to contain fewer British thermal units than the crude oil from which it was produced. I

have discovered that the distillation can be carried on at a sufficiently. low temperature to avoid'said destructive distillation and the consequent loss of asphalt, and that the pressure under which the distillation and separation take place should be but little if any above atmospheric pressure in order to secure the best results. The evaporating pan has a solid bottom and the asphalt solution must cover the same from end to end to facilitate evaporation. The hot asphalt therein prevents condensation and dropping back of vapors from the charge .below.

I have discovered that by the apparatus above described, and by distilling at atmospheric pressure and at a comparatively low temperature, asfor instance, a temperature of 400 to'600 degrees Fahrenheit, provision is made for producing a superior asphalt cement without destructive distillation of the oil. That is to say, with the old process a portion of the asphalt was transmuted into oil, and together with more or less sulfurpassed into the oil products to their injury, and to the detrimentv and impoverishment of the'asphalt cement and at the same time-a destructive distillation of the oil was effected, all ofwhich is avoided by thisnew treatment. Such former destructive distillation released sulfur vapors and free hydrogen which afterward unite in the condensed vapors to form sulfu retted hydrogen in the resultant oil.

. One ofthe products under the old method was a. sulfureted hydrogen gas which indicated a loss by destructive distillation. Such gas carried away, fromthe products a good proportion of the hydrocarbons of the oil.

Furthermore,'a carbonaceous deposit insoluble in carbon-tetrachlorid was left inthe asphalt.

By my newly-invented processthe roduction of sulfureted hydrogen is avoi ed, and the vapors, which issue through the out lets intended for emission of vapors from the newly-invented extractor, are hydrocare bon vapors which, when condensed, formhydrocarbon oils; so that the products of this new method of distillation consist of a vulcanized asphalt cement and pure hydrocarbon oils separated from each other with a minimum loss through non-condensable vapors. y

The saving by this new method amounts to approximately four per cent, more or less,

over the former methods. That is to say, with former methods there .was a loss of approximately six per cent., more or less, of the values, and I avoid about per cent. of such loss. Furthermore, the asphalt produced by this method is superior to the asphalts produced by former methods because it is free from any products of destructive distillation.

By my invention and discovery I am enabled to obtain from a given oil 65 parts asphaltum as compared with 40 parts ascommonlytermed an agitator, and into thebottom of which a blast of compressed air is introduced; so that the sulfuric acid (isscending through the mass by the force of gravity will come into intimate relation with all the contents of the receptacle. After the contents of the receptacle have been thoroughly mixed with the sulfuricacid the mass is allowed to stand at rest until the sulfuric acid and the elements that have combined therewith settle to the bot-tomand are drawn ofi'.- The product thus drawn ofi is termed sludge.

The oils from former processes when treated with sulfuric acid show a strong reaction which is not apparent with. the oil produced by my new process. With the old process a comparatively large amount of sludge is produced by the acid treatment, while with the oils produced by my present process the acid treatment producesonly a small amount of sludge, thus showing that there is only a very small proportion of inferior oils.

In practice acharge of crude oil sufficient to fill the extractor about half full will be put into the extractor and brought to the required temperature of about and somewhat above 400 degrees Fahrenheit and will be maintained at about that temperature until the products have been made and drawn from the extractor. Then another charge of crude oil will be supplied and reduced as before, and so on.

After the oil has been brought to the required temperature the pump will be started into operation thereby drawing the hot oil from the bottom of the extractor and pouring it into the evaporating pan, whence it may overflow to the top of the charge thus continually bringing the hottest oil up into the space above the charge of oil.

At the outset of the process a consider able outflow of vapors will issue from the vapor-pipes. 11 and no products will flow from the'pipes 10; but as the process con-' tinues, products begin to flow from the oilpipes 10 and the outflow of such products increases while the outflow of products from the upper pipes 11 gradually decreases. Furthermore, the gravity of the product. from the lower pipes 13 gradually increases as the process continues, until the oil is all expelled from the charge and only asphalt remains in the extractor, which may. then be emptied by drawing off the hot asphalt through the pipe 4. It is thus seen that the purpose of the outlets 11 is simply to remove the lighter vapors which might produce pressure inside the shell, but it is understood that while the apparatus is more effective with the outlets 11 arranged as shown approximately at and below the level of the top of the shell, the production of the asphaltic cement'may be effected without withdrawing lighter vapors from the top of the shell, and that the outlets 10 may be depended upon entirely to remove the vapors without departing from the broad spirit of this invention.

By providing a shell of cylindrical form the outlets 11 are readily arranged in the most efiective manner so that they can carry off all of the vapors which are able to arise to the top of the shell without carrying off the vapors which lie below the level of the outlet. A distinction is to be.observcd between the operation thus etlected and that which would occur if a pipe or a dome were to open upwardfrom the shell for the purpose of discharging-the lighter-"vapors, in that in the form shown in the drawings the vapors at the top of the shell flow olf practically by their own gravity without piling up and increasing the pressure in the -Il'ltLIlner which occurswhen a dome or a gooseneck elevated above the 'shell is employed.

The principle of this invention is to eliminatethe oils by condensing the vapors and ing of the asphalt.

carrying them off at minimum pressure and without forcing the still so that there is no danger of destructive distillation or crack .I claim: 1. The method of obtaining asphalt from asphaltic oils which consists in heating the oil to a' temperature between 400 and 600 degrees Fahrenheit'within a shell, removing oil from the lower portion of the shell to the upperportion of the shell and there subjecting the same to the temperature of the "she'll above the surface of the lower chargeupper portion of the shell, and means near.

' the median'portion of the shell to carry 0E heavy vapors and condensation from the 'Walls ofthe shell,'of an evaporating-pan in the shell above the last-named means, and means for transferring liquid front the lower part' of the shell to said evaporatingpan: 4

extractor, for obtaining asphalt comprising a shell,-an evaporating-pan in the iipper portion of the shell, means for transferrin liquid from the lower portion of thexshe lmeans for collecting and discharging the to said evaporating-pan, and

products of condensation from the walls of the shell.

4. Apparatus for obtaining asphalt-cementfroi'n asphalt solutions, comprisin an approximately horizontal cylindrical s ell,

means to heat the shell, means for carrying off uncondensed vapors from the upper portion of the shell, means near the median portion of the shell to carry ofi heavy vapors and products of condensation fromthe walls of the shell, an evaporating-pan in the shell above the last-named means, and means for transferring liquid from the lowervpart of i the shell to said evaporating-pan.

The method of obtaining asphalt from ,asphaltic oils, which consists in heating the oil-to a temperature-between .400 and'600 degrees Fahrenheit within a shell, removing oil from the lower portion of the shell to the upper portion and there maintai'ning a charge: of such removed oil, subjecting such charge to the temperature of the shell above the surface of thelower charge of oil, causing a flow of oil from the upper to the lower charge, and removing from below the' top of the shell the products arising from said charges.

In testimony whereof, I have hereunto set my hand at Los Angeles, California, this 10th day of February, 1908.

' FRANKLIN H. DUNHAM. In presence of JAMES R. TOWNSEND, J ULIa TOWNSEND. 

